1. Field of the Invention
This invention pertains to communications, and more particularly, to a late binding communication system and method for real-time communication of time-based media.
2. Description of Related Art
Currently there are three globally used addressing domains. The postal system, which is mainly used for the delivery of letters and parcels, relies on the use of a physical address, such as a house address, office building address or Post Office (PO) box. In order to assure the delivery of a letter or parcel, the physical address of the recipient must be provided, including a country, state or territory, a city or town, postal or zip code, street name and street number. The existing telephone infrastructure defines another global addressing domain that has historically been used for near real-time voice communications (i.e., telephone calls). Both land-line and mobile telephones are addressed (i.e., called) using a telephone number, which typically includes a country code and a variable number of additional digits to identify a particular phone within a given country and/or area code. When a circuit connection is made between the calling parties, a full duplex conversation may take place. A third global addressing system is email. Every email account is identified by a unique globally addressable email address, which defines a user name and a domain name.
Emails are typically text messages that are sent from a sender to one or more recipients. The emails are created on an email client. One well-known email client is Microsoft Outlook, which is used to create, receive and manage email messages on a computer. Alternatively, free email services like Yahoo, Google or Hotmail are available to users through a web page. Regardless of the type used, an email client will typically (i) list or display all the received messages, with an email header showing the subject of the email, the sender of the email, the date/time it was sent and possibly other attributes such as the size of the email; (ii) allow the user to select messages for review; (iii) allow the user to type and send new messages to recipients and reply to the received emails of others; and (iv) allow attachments, such as still photos, documents, or video clips, to be attached to an out-going email.
An email message must first be created in full before it can be sent. A sender will typically first define a recipient by entering their email address into the appropriate “To” field in the header of the email. The text message is then typed into the body of the email and files may optionally be attached. When the message is complete, the user sends the email. During the send sequence, the email client initiates a session with its email server located on a network. This session is typically established with the Simple Mail Transport Protocol (SMTP). During the session, the email client provides the SMTP server with the email address of the sender, the email address of the recipient, and the body of the email with any attachments. The email addresses of the recipient is segmented into two parts, including the recipient's name (e.g., “jsmith”) and the domain name (e.g., “hotmail.com”). If the recipient is in a domain that the SMTP server controls, then the server carries out delivery instructions for the specific recipient, which is typically delivery of the email to an in-box associated with the recipient on the same SMTP server or another server located in the same domain. On the other hand if the recipient is in a domain that the server does not control, then the email server needs to communicate with a server that controls the recipient's domain using SMTP.
To send the email to the recipient in another domain, the SMTP server initiates a conversation with the Domain Name System (DNS), asking for the Mail eXchanger (MX) record of the recipient's domain. This MX record contains a prioritized list of SMTP servers for that domain. The email is then sent from the SMTP server of the sender to the first SMTP server in the MX list that responds. This first responding server then determines if the recipient is in the domain the first responding server controls. If so, the email is delivered to the inbox of the recipient. If not, the above-described process is repeated until a responding server is the one that can deliver the message into the recipient's inbox. Each server along the delivery route is sometimes referred to as a “hop”. Once in the inbox, the email may be accessed through the email client of the recipient, which may be located on the computer of the recipient or on the Internet. If an email is sent to multiple parties, the above-described process is repeated for each recipient.
The above-described sequence generally applies for emails sent over the Internet. With certain proprietary systems, such as an email sent between two Microsoft Exchange users on the same proprietary network, the SMTP protocol may not be used for routing the email but email addresses are still used. The operation of the proprietary protocol and server is essentially the same as SMTP.
The existing email infrastructure, regardless if it relies on SMTP or a proprietary email protocol, is essentially a “store and forward” messaging system. An email message must first be created in its entirety before it can be sent. At the SMTP or proprietary mail server of the sender, as well as any intermediate email server hops along the path to the SMTP or proprietary mail server of the recipient, the email message must be received in full before it can be forwarded. Finally the email must be received in full at the inbox of the recipient before the recipient can review the message.
By way of comparison, telephone conversations over the Public Switched Telephone Network (PSTN) are progressive in nature. As words are spoken, they are simultaneously transmitted from the sender to the recipient, where they are heard effectively live or near real-time. As a result, telephone conversations can be conducted in a “live” or near real-time mode through a common network connection (i.e., a circuit). Email communication in contrast usually occurs through a series of separate store and forward messages, often sent back and forth between two or more parties at distinct times, across a network, such as the Internet.
It is well known to attach a file to an email containing time-based media (i.e., media that changes with respect to time), such as a video clip. The time-based media attached to an email message, however, can never be reviewed by a recipient “live”, as it is being created, due to the store and forward nature of email. Rather the email and the attachment containing the time-based media must first be created, sent, stored and forwarded at each email server hop on the network, and then received by the recipient in full before the time-based media of the attachment can be reviewed. It is therefore not possible for the recipient of an email message to review the media in near real-time as the media is being created.
Telephone messaging systems are also known where a voice message may be created and sent to a recipient in the form of an email. With these systems, the Public Switched Telephone Network (PSTN) is used in cooperation with emails. In use, a recording of the message must first be made, stored, and then forwarded to the recipient by email. Again, however, the message must first be received in full before the recipient can review the recorded message.
Instant messaging or IM is another example of a store and forward system. Similar to email as described above, messages must be completed before they can be forwarded to a recipient. Messages in IM systems are generally much shorter than those sent via email. Each line of text in IM systems is a separate message delivered in a store and forward manner. Existing IM systems do not provide a way for a recipient to progressively and simultaneously review a message as the sender creates the message.
“Live” text systems are well known, although they were mostly used on early Unix systems with dumb terminal interfaces. These text systems, give the appearance of being “live” since each individual keystroke is sent to the recipient as soon as the sender pressed that key. But in reality, these systems are actually store and forward based, where the transmission of each keystroke is a discrete event. These systems are for text only (i.e., non time-based media only) and they do not allow the recipient to progressively review the media in real-time per se.
In the context of communications, a recipient address can be described as “bound” when a valid delivery path across the network has been determined for that address. Conventional telephone calls over the PSTN are said to use “early binding” because the dialed phone number, the “recipient address” in this case, is used to establish some active path (i.e., a circuit connection) to the recipient before any media can be transmitted to the recipient. Only after the connection is made can the caller begin speaking and the media transmitted. Regardless if the call is placed to one or more telephone numbers, or the call is transferred to a voice messaging system, the binding typically occurs before any words can be delivered. Since the binding of the recipient's address to an active destination on the network happens before any transmission of media, it is said to be “early”. In contrast, emails are said to employ “late” binding. A person may compose an email message and send it over a network without binding that message to the device on which the recipient will consume it. Instead, after the email is composed, the email address of the recipient is used to route the email to the recipient to be reviewed on a device and at a time of the recipient's choosing. Since late binding systems require the completion of a message before it can be sent, late binding systems cannot be used for “live” communication.